255 research outputs found
Taking Quantitative Genomics into the Wild
A key goal in studies of ecology and evolution is understanding the causes of
phenotypic diversity in nature. Most traits of interest, such as those relating
to morphology, life-history, immunity and behaviour are quantitative, and
phenotypic variation is driven by the cumulative effects of genetic and
environmental variation. The field of quantitative genetics aims to quantify
the additive genetic component of this trait variance (i.e. the
"heritability"), often with the underlying assumption that trait variance is
driven by many loci of infinitesimal effects throughout the genome. This
approach allows us to understand the evolutionary potential of natural
populations and can be extended to examine the genetic covariation with fitness
to predict responses to selection. Therefore, quantitative genetic studies are
fundamental to understanding evolution in the wild. Over the last two decades,
there has been a wealth of studies investigating trait heritabilities and
genetic correlations, but these were initially limited to long-term studies of
pedigreed populations or common-garden experiments. However, genomic
technologies have since allowed quantitative genetic studies in a more diverse
range of wild systems and has increased the opportunities for addressing
outstanding questions in ecology and evolution. In particular, genomic studies
can uncover the genetic basis of fitness-related quantitative traits, allowing
a better understanding of their evolutionary dynamics. We organised this
special issue to highlight new work and review recent advances at the cutting
edge of "Wild Quantitative Genomics". In this Editorial, we will present some
history of wild quantitative genetic and genomic studies, before discussing the
main themes in the papers published in this special issue and highlighting the
future outlook of this dynamic field.Comment: 17 page (plus references) Editorial for a special issue of
Proceedings of the Royal Society B: Biological Sciences. Revised submissio
The relationship between body positioning, muscle activity, and spinal kinematics in cyclists with and without low back pain
Objectives: To determine if relationships exist between body positioning, spinal kinematics, and muscle activity in active cyclists with non-traumatic LBP. To explore variations in optimal positioning and bike set up in order to address variables associated with LBP in the physical therapy clinic.https://jdc.jefferson.edu/dptcapstones/1003/thumbnail.jp
The observable properties of galaxy accretion events in Milky Way-like galaxies in the FIRE-2 cosmological simulations
In the -Cold Dark Matter model of the Universe, galaxies form in
part through accreting satellite systems. Previous work have built an
understanding of the signatures of these processes contained within galactic
stellar halos. This work revisits that picture using seven Milky Way-like
galaxies in the \textit{Latte} suite of FIRE-2 cosmological simulations. The
resolution of these simulations allows a comparison of contributions from
satellites above M10M, enabling the
analysis of observable properties for disrupted satellites in a fully
self-consistent and cosmological context. Our results show that, the time of
accretion and the stellar mass of an accreted satellite are fundamental
parameters that in partnership dictate the resulting spatial distribution,
orbital energy, and [/Fe]-[Fe/H] compositions of the stellar debris of
such mergers . These parameters also govern the resulting
dynamical state of an accreted galaxy at , leading to the expectation that
the inner regions of the stellar halo (R 30 kpc)
should contain fully phase-mixed debris from both lower and higher mass
satellites. In addition, we find that a significant fraction of the lower mass
satellites accreted at early times deposit debris in the outer halo
(R 50 kpc) that are fully phased-mixed, indicating
that they could be identified in kinematic surveys. Our results suggest that,
as future surveys become increasingly able to map the outer halo of our Galaxy,
they may reveal the remnants of long-dead dwarf galaxies whose counterparts are
too faint to be seen in higher redshift surveys.Comment: Submitted for publication in Ap
On the co-rotation of Milky Way satellites: LMC-mass satellites induce apparent motions in outer halo tracers
Understanding the physical mechanism behind the formation of a co-rotating
thin plane of satellite galaxies, like the one observed around the Milky Way
(MW), has been challenging. The perturbations induced by a massive satellite
galaxy, like the Large Magellanic Cloud (LMC) provide valuable insight into
this problem. The LMC induces an apparent co-rotating motion in the outer halo
by displacing the inner regions of the halo with respect to the outer halo.
Using the Latte suite of FIRE-2 cosmological simulations of MW-mass galaxies,
we confirm that the apparent motion of the outer halo induced by the infall of
a massive satellite changes the observed distribution of orbital poles of
outer-halo tracers, including satellites. We quantify the changes in the
distribution of orbital poles using the two-point angular correlation function
and find that all satellites induce changes. However, the most massive
satellites with pericentric passages between 30-100kpc induce the largest
changes. The best LMC-like satellite analog shows the largest change in orbital
pole distribution. The dispersion of orbital poles decreases by 20{\deg} during
the first two pericentric passages. Even when excluding the satellites brought
in with the LMC-like satellite, there is clustering of orbital poles. These
results suggest that in the MW, the recent pericentric passage of the LMC
should have changed the observed distribution of orbital poles of all other
satellites. Therefore, studies of kinematically-coherent planes of satellites
that seek to place the MW in a cosmological context should account for the
existence of a massive satellite like the LMC.Comment: 20 pages, 10 figures. ApJ submitted, Comments are welcom
Photometric Redshifts of Quasars
We demonstrate that the design of the Sloan Digital Sky Survey (SDSS) filter
system and the quality of the SDSS imaging data are sufficient for determining
accurate and precise photometric redshifts (``photo-z''s) of quasars. Using a
sample of 2625 quasars, we show that photo-z determination is even possible for
z<=2.2 despite the lack of a strong continuum break that robust photo-z
techniques normally require. We find that, using our empirical method on our
sample of objects known to be quasars, approximately 70% of the photometric
redshifts are correct to within delta z = 0.2; the fraction of correct
photometric redshifts is even better for z>3. The accuracy of quasar
photometric redshifts does not appear to be dependent upon magnitude to nearly
21st magnitude in i'. Careful calibration of the color-redshift relation to
21st magnitude may allow for the discovery of on the order of 10^6 quasars
candidates in addition to the 10^5 quasars that the SDSS will confirm
spectroscopically. We discuss the efficient selection of quasar candidates from
imaging data for use with the photometric redshift technique and the potential
scientific uses of a large sample of quasar candidates with photometric
redshifts.Comment: 29 pages, 8 figures, submitted to A
Real-time pandemic surveillance using hospital admissions and mobility data
Forecasting the burden of COVID-19 has been impeded by limitations in data, with case reporting biased by testing practices, death counts lagging far behind infections, and hospital census reflecting time-varying patient access, admission criteria, and demographics. Here, we show that hospital admissions coupled with mobility data can reliably predict severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission rates and health-care demand. Using a forecasting model that has guided mitigation policies in Austin, TX, we estimate that the local reproduction number had an initial 7-d average of 5.8 (95% credible interval [CrI]: 3.6 to 7.9) and reached a low of 0.65 (95% CrI: 0.52 to0.77) after the summer 2020 surge. Estimated case detection rates ranged from 17.2% (95% CrI: 11.8 to 22.1%) at the outset to a high of 70% (95% CrI: 64 to 80%) in January 2021, and infection prevalence remained above 0.1% between April 2020 and March 1, 2021, peaking at 0.8% (0.7-0.9%) in early January 2021. As precautionary behaviors increased safety in public spaces, the relationship between mobility and transmission weakened. We estimate that mobility-associated transmission was 62% (95%CrI: 52 to 68%) lower in February 2021 compared to March 2020. In a retrospective comparison, the 95% CrIs of our 1, 2, and 3 wk ahead forecasts contained 93.6%, 89.9%, and 87.7% of reported data, respectively. Developed by a task force including scientists, public health officials, policy makers, and hospital executives, this model can reliably project COVID-19 healthcare needs in US cities.This work was supported by Grant U01IP001136 from the CDC, Grant NIH R01 AI151176 from the NIH, and a generous donation from Tito’s Handmade Vodka.StatisticsIntegrative BiologyOperations Research and Industrial EngineeringTexas Advanced Computing Center (TACC)Dell Medical SchoolInformation, Risk, and Operations Management (IROM
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Cancer is the fourth leading cause of death in adolescent and young adults (AYA: ages15-39) worldwide. Over 90% of AYAs with cancer live in low-and-middle-incomecountries (LMIC). Little is known about thecurrent landscape of AYA oncology care in these settings. Guidelines for the care of thisunique population in LMIC in Latin America are lacking
Canvass: a crowd-sourced, natural-product screening library for exploring biological space
NCATS thanks Dingyin Tao for assistance with compound characterization. This research was supported by the Intramural Research Program of the National Center for Advancing Translational Sciences, National Institutes of Health (NIH). R.B.A. acknowledges support from NSF (CHE-1665145) and NIH (GM126221). M.K.B. acknowledges support from NIH (5R01GM110131). N.Z.B. thanks support from NIGMS, NIH (R01GM114061). J.K.C. acknowledges support from NSF (CHE-1665331). J.C. acknowledges support from the Fogarty International Center, NIH (TW009872). P.A.C. acknowledges support from the National Cancer Institute (NCI), NIH (R01 CA158275), and the NIH/National Institute of Aging (P01 AG012411). N.K.G. acknowledges support from NSF (CHE-1464898). B.C.G. thanks the support of NSF (RUI: 213569), the Camille and Henry Dreyfus Foundation, and the Arnold and Mabel Beckman Foundation. C.C.H. thanks the start-up funds from the Scripps Institution of Oceanography for support. J.N.J. acknowledges support from NIH (GM 063557, GM 084333). A.D.K. thanks the support from NCI, NIH (P01CA125066). D.G.I.K. acknowledges support from the National Center for Complementary and Integrative Health (1 R01 AT008088) and the Fogarty International Center, NIH (U01 TW00313), and gratefully acknowledges courtesies extended by the Government of Madagascar (Ministere des Eaux et Forets). O.K. thanks NIH (R01GM071779) for financial support. T.J.M. acknowledges support from NIH (GM116952). S.M. acknowledges support from NIH (DA045884-01, DA046487-01, AA026949-01), the Office of the Assistant Secretary of Defense for Health Affairs through the Peer Reviewed Medical Research Program (W81XWH-17-1-0256), and NCI, NIH, through a Cancer Center Support Grant (P30 CA008748). K.N.M. thanks the California Department of Food and Agriculture Pierce's Disease and Glassy Winged Sharpshooter Board for support. B.T.M. thanks Michael Mullowney for his contribution in the isolation, elucidation, and submission of the compounds in this work. P.N. acknowledges support from NIH (R01 GM111476). L.E.O. acknowledges support from NIH (R01-HL25854, R01-GM30859, R0-1-NS-12389). L.E.B., J.K.S., and J.A.P. thank the NIH (R35 GM-118173, R24 GM-111625) for research support. F.R. thanks the American Lebanese Syrian Associated Charities (ALSAC) for financial support. I.S. thanks the University of Oklahoma Startup funds for support. J.T.S. acknowledges support from ACS PRF (53767-ND1) and NSF (CHE-1414298), and thanks Drs. Kellan N. Lamb and Michael J. Di Maso for their synthetic contribution. B.S. acknowledges support from NIH (CA78747, CA106150, GM114353, GM115575). W.S. acknowledges support from NIGMS, NIH (R15GM116032, P30 GM103450), and thanks the University of Arkansas for startup funds and the Arkansas Biosciences Institute (ABI) for seed money. C.R.J.S. acknowledges support from NIH (R01GM121656). D.S.T. thanks the support of NIH (T32 CA062948-Gudas) and PhRMA Foundation to A.L.V., NIH (P41 GM076267) to D.S.T., and CCSG NIH (P30 CA008748) to C.B. Thompson. R.E.T. acknowledges support from NIGMS, NIH (GM129465). R.J.T. thanks the American Cancer Society (RSG-12-253-01-CDD) and NSF (CHE1361173) for support. D.A.V. thanks the Camille and Henry Dreyfus Foundation, the National Science Foundation (CHE-0353662, CHE-1005253, and CHE-1725142), the Beckman Foundation, the Sherman Fairchild Foundation, the John Stauffer Charitable Trust, and the Christian Scholars Foundation for support. J.W. acknowledges support from the American Cancer Society through the Research Scholar Grant (RSG-13-011-01-CDD). W.M.W.acknowledges support from NIGMS, NIH (GM119426), and NSF (CHE1755698). A.Z. acknowledges support from NSF (CHE-1463819). (Intramural Research Program of the National Center for Advancing Translational Sciences, National Institutes of Health (NIH); CHE-1665145 - NSF; CHE-1665331 - NSF; CHE-1464898 - NSF; RUI: 213569 - NSF; CHE-1414298 - NSF; CHE1361173 - NSF; CHE1755698 - NSF; CHE-1463819 - NSF; GM126221 - NIH; 5R01GM110131 - NIH; GM 063557 - NIH; GM 084333 - NIH; R01GM071779 - NIH; GM116952 - NIH; DA045884-01 - NIH; DA046487-01 - NIH; AA026949-01 - NIH; R01 GM111476 - NIH; R01-HL25854 - NIH; R01-GM30859 - NIH; R0-1-NS-12389 - NIH; R35 GM-118173 - NIH; R24 GM-111625 - NIH; CA78747 - NIH; CA106150 - NIH; GM114353 - NIH; GM115575 - NIH; R01GM121656 - NIH; T32 CA062948-Gudas - NIH; P41 GM076267 - NIH; R01GM114061 - NIGMS, NIH; R15GM116032 - NIGMS, NIH; P30 GM103450 - NIGMS, NIH; GM129465 - NIGMS, NIH; GM119426 - NIGMS, NIH; TW009872 - Fogarty International Center, NIH; U01 TW00313 - Fogarty International Center, NIH; R01 CA158275 - National Cancer Institute (NCI), NIH; P01 AG012411 - NIH/National Institute of Aging; Camille and Henry Dreyfus Foundation; Arnold and Mabel Beckman Foundation; Scripps Institution of Oceanography; P01CA125066 - NCI, NIH; 1 R01 AT008088 - National Center for Complementary and Integrative Health; W81XWH-17-1-0256 - Office of the Assistant Secretary of Defense for Health Affairs through the Peer Reviewed Medical Research Program; P30 CA008748 - NCI, NIH, through a Cancer Center Support Grant; California Department of Food and Agriculture Pierce's Disease and Glassy Winged Sharpshooter Board; American Lebanese Syrian Associated Charities (ALSAC); University of Oklahoma Startup funds; 53767-ND1 - ACS PRF; PhRMA Foundation; P30 CA008748 - CCSG NIH; RSG-12-253-01-CDD - American Cancer Society; RSG-13-011-01-CDD - American Cancer Society; CHE-0353662 - National Science Foundation; CHE-1005253 - National Science Foundation; CHE-1725142 - National Science Foundation; Beckman Foundation; Sherman Fairchild Foundation; John Stauffer Charitable Trust; Christian Scholars Foundation)Published versionSupporting documentatio
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